Heh, might as well jump on the band-wagon. I added military civics as the sixth option, so they're not intended to replace anything. While the names and techs differ somewhat, they're eerily similar to Optimizer's setup.
Militia (default) - No upkeep (since it's the sixth category)
Your basic Oh-My-God-is-this-the-best-we-can-do?-we're-all-gonna-die!-rabble
Levy (Civil Service) - Military produced with food
Seemed like the one civic where the effect would fit. Much like militia, but less momentary.
Mercenary (Currency) - +50% Military production, -25% WW, +1 gold per unit
This is also supposed to represent an early Professional Army (they're all paid killers anyway

). The pay attracts more people to join the ranks, hence the unbalancing MP-bonus.
Standing Forces (Gunpowder) - +25% MP, -50% WW, +1 GPU, +2 XP
Way over the top? Not with "Very High Upkeep" (a new upkeep category). Supposed to represent a uniformed, permanent defense force. A bit problematic to place on the tech tree, given that Standing Forces existed before emerging in 17th century Europe, but anyhoo. A little more "eurocentrism" don't make much difference.
Conscription (Constitution) - +3 Conscripts, free units, +25% WW.
See, a choice between following the upper or lower branch to a military civic, and not one which further benefits beelining to cavalry. With the war weariness hit (which warrants a corresponding -25% WW from Nationhood IMO), this is supposed to be a cheap, defensive alternative to SF.
Regardless of which military civic-pattern you go by, most, if not all, Aggressive leaders should have favorite civics in this category.